Rings were worn on fingers before recorded history. The problems concerning fit that the first people to wear rings experienced are still with us today. These fit problems relate to initial fit of a ring when the ring is first acquired and changes in finger size with age. A child's finger grows longer and larger in diameter until the child becomes an adult. The fingers of an adult change as the adults weight changes. Injuries can also change finger size. The knuckle joint connecting the first phalanx to the second phalanx of each finger tends to increase in diameter with age. At the same time the diameter of the first phalanx and the tissue encasing the first phalanx tends to decrease in diameter with advancing age when weight remains substantially constant. When the knuckle joint is larger in diameter than the center portion of the first phalanx, finger rings are loose after they slide over the knuckle joint.
Finger rings that are a band with a uniform cross section can rotate about a finger when they are loose. Such rotation of a band is not generally objectionable as long as the rings do not fall off.
Most finger rings worn by people today have a shank portion that extends radially outward from the band and carries an ornamentation. Such shank portions are intended to face outwardly from the backside of the hand when the fingers are extended. Rotation of a finger ring with a shank portion tends to move the shank portion and ornamentation carried by the shank portion out of view. When the shank portion rotates to a position between two fingers, it may interfere with the ability to use the fingers and to grasp various objects. To reduce these problems, a person wearing a loose ring has to rotate the ring back to the desired orientation frequently.
Numerous devices have been employed to tighten a loose finger ring and prevent rotation relative to a finger. One of the simplest devices is a band of adhesive tape wrapped around a section of the ring band. The tape band reduces the diameter of the finger passage through the ring band however the finger passage diameter must remain sufficiently large to slide over a knuckle. The tape wrap works but is unattractive and requires frequent replacement. Various mechanical devices have been tried to tighten loose rings. One group of mechanical devices includes a wedge member that is moved into a position between an inside surface of the band and a finger. Mechanical devices include levers that pivot about an axis parallel to the ring finger passage and into the finger passage through a ring. Some of these levers are spring biased. Springs and levers are expensive to manufacture, generally require substantial modification of the ring, and require maintenance.
Resilient pads have also been proposed to prevent rotation of finger rings relative to a finger. These pads require some machining of the ring, require a ring to be larger in diameter than normal, are difficult to adjust and tend to collect dirt and oils and require frequent cleaning. Resilient pads can be compressed slightly to slide over knuckles. However, such pads may have an adhesive coating that resists ring rotation and also resists passage of a knuckle.
Devices to adjust finger ring diameters are not readily available for purchase. Although the need for such devices is well known, none of the devices developed in the past appear to have found substantial acceptance.